The tracheal bronchial catheters generally in use consist of an elongated tube with a preformed single bend of about 30.degree. away from the normally straight shank of the tube and there is usually a coupling at the proximal end as a suction thumb control device. The difficulty has been that when such a single bend catheter is inserted down the traches the tip at the end of the single bend invariably enters the right main bronchus. Despite twisting around the axis of the catheter it is virtually impossible to cause the bent tip to enter the main left bronchus, unless the patient is being fluoroscoped so that the surgeon can see the tip and gradually induce it to enter the left main bronchus and thence enter the upper and lower lobar bronchus.
Tubular instruments having various types and shapes of bends at the distal end have heretofore been proposed for use in various types of surgery.
For example, U.S. Pat. No. 1,931,720 to Edgington of Oct. 24, 1933 discloses a triple bent tube, apparently of metal, for cleaning the eustachian tubes or pharynx, but two such tubes are required to treat the right and the left.
U.S. Pat. No. 3,807,401 to Riggle, et al of Apr. 30, 1974 also discloses a double bent, hollow tube as a suction device, but the tube is of metal and rigid.
U.S. Pat. No. 3,920,023 to Dye, et al of Nov. 18, 1975 discloses a catheter in the form of a rigid, curved, hollow tube curved for insertion into the bladder.
U.S. Pat. No. 4,068,664 to Sharp, et al of Jan. 17, 1978 discloses a plurality of differently shaped adapter tubes all of which are of rigid material.